<html> 
<head>
<meta charset="utf-8">
<script src='jquery-3.2.1.min.js'></script>
</head>
<body> 
<label for="select_city">城市</label> 
<form action='city_lian.php' method="post">
<div data-role="controlgroup" id="select_p_c_a" data-ajax="false"> 
 <select id="select_province" name='p'></select> 
 <select id="select_city" name='c'></select> 
 <select id="select_area" name='a'></select> 
<select name="cars">
<option value="volvo">Volvo</option>
<option value="saab">Saab</option>
<option value="fiat" selected="selected">Fiat</option>
<option value="audi">Audi</option>
</select>
</div> 
 <input type="submit" value="Submit" />
</form>
<script src="test.js"></script> 
</body> 
</html> 
  
<script> 
 region_init("select_province","select_city","select_area"); 
</script> 
</body> 
</html>